# Relationship history for MSHA mine 0503097

Current hierarchy: **Carl Richard → National Energy Resources Inc → Baldy Canyon**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Cissey Lee Coal Company → Baldy Canyon; 1977-09-01 to 1979-02-09; source msha-controller-operator-history
- **controller_controls_mine:** Vesper C J → Baldy Canyon; 1977-09-01 to 1979-02-09; source msha-controller-operator-history
- **controller_controls_operator:** Vesper C J → Cissey Lee Coal Company; 1977-09-01 to 1979-02-09; source msha-controller-operator-history
- **operator_operates_mine:** National Energy Resources Inc → Baldy Canyon; 1979-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Carl Richard → Baldy Canyon; 1979-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carl Richard → National Energy Resources Inc; 1979-02-10 to current/open; source msha-controller-operator-history